Effects of Nitrogen Fertilizer and Biochar Application Rate Interaction on Growth and Root-Knot Nematode Disease of Greenhouse Tomatoes
To explore the effects of combined application of nitrogen fertilizer and biochar interaction on tomato growth and root-knot nematode disease,a suitable nitrogen fertilizer application rates and biochar application rates were screened.A two-factor three-level randomized block pot experiment design was adopted to study three nitrogen application rates(N1:0 mg/kg soil,N2:200 mg/kg soil,N3:400 mg/kg soil)and three biochar application rates(C1:0 g/kg soil,C2:2 g/kg soil,C3:4 g/kg soil)were used this study.The effects of different treatments on tomato growth,yield,quality,photosynthetic characteristics and root-knot nematode indicators were analyzed under different combinations of treatments.The results showed that the effects of nitrogen fertilizer,biochar and their interaction on tomato growth,yield and quality,photosynthetic characteristics and root-knot nematode indicators all reached extremely significant(P<0.01)or significant(P<0.05)level.With the increase of nitrogen fertilizer and biochar application,the growth,photosynthetic characteristics,yield and quality of tomatoes were showed a trend of firstly increased and then decreased.The number of root nodules,root-knot nematodes and eggs were showed a trend of firstly decreased and then increased,reached the lowest value under the N2C3 treatment combination;The leaf area,net photosynthetic rate,yield and vitamin C of the N2C3 treatment combination were reached significant than other treatment combinations.The number of root-knot nematodes and eggs were significantly lower than other treatment combinations.Therefore,in the facility soil(total nitrogen 1.52 g/kg,available phosphorus 191.9 mg/kg,and available potassium 323 mg/kg)infected with root-knot nematode disease in the Hexi area of Gansu province,the condition of 200 mg/kg nitrogen fertilizer of soil and 4 g/kg biochar of soil was conducive to tomato growth and quality,and had a good control effect on root-knot nematode disease.